Checkpoint: preserve all uncommitted rust-rewrite worktree work

Safety commit before reconciling this worktree with main, which has
diverged with its own separate fixes today. Nothing here is reviewed
or curated yet - this exists purely so none of this work can be lost
to a git operation, disk issue, or worktree cleanup while that
reconciliation happens.

1 files changed, 52 insertions, 0 deletions

diff --git a/crates/wayland/src/protocols/selection.rs b/crates/wayland/src/protocols/selection.rs
new file mode 100644
index 0000000..fadb0ca
--- /dev/null
+++ b/crates/wayland/src/protocols/selection.rs
@@ -0,0 +1,52 @@
+//! Clipboard/primary-selection/drag-and-drop.
+//!
+//! All three selection protocols below (`wl_data_device_manager`,
+//! `zwp_primary_selection_v1`, `zwlr_data_control_manager_v1`) share
+//! smithay's single `SelectionHandler`. Every transfer here is
+//! *client-to-client*: one client owns the selection and writes the bytes
+//! itself, and smithay wires the two ends together without the data passing
+//! through us. `send_selection` is only ever called for a
+//! **compositor-provided** selection (one this WM set itself via
+//! `set_data_device_selection`), which srdwm never does - so it is
+//! deliberately left unimplemented rather than faked.
+
+use smithay::wayland::selection::data_device::{ClientDndGrabHandler, DataDeviceHandler, DataDeviceState, ServerDndGrabHandler};
+use smithay::wayland::selection::primary_selection::{PrimarySelectionHandler, PrimarySelectionState};
+use smithay::wayland::selection::wlr_data_control::{DataControlHandler, DataControlState};
+use smithay::wayland::selection::SelectionHandler;
+
+use crate::state::CompState;
+
+impl SelectionHandler for CompState {
+    type SelectionUserData = ();
+}
+
+impl DataDeviceHandler for CompState {
+    fn data_device_state(&self) -> &DataDeviceState {
+        &self.data_device_state
+    }
+}
+
+// Drag-and-drop: the default trait methods already do the right thing for a
+// compositor that doesn't draw its own drag icon or offer server-side drag
+// sources - smithay runs the pointer grab and the offer/accept negotiation
+// internally. Both are implemented empty (rather than skipped) because
+// `DataDeviceHandler` requires them as supertraits.
+impl ClientDndGrabHandler for CompState {}
+impl ServerDndGrabHandler for CompState {}
+
+impl PrimarySelectionHandler for CompState {
+    fn primary_selection_state(&self) -> &PrimarySelectionState {
+        &self.primary_selection_state
+    }
+}
+
+/// `zwlr_data_control_manager_v1`: lets a client read/watch the selection
+/// without ever holding keyboard focus. This is what `wl-paste --watch`
+/// (and thus `cliphist store`, which the user's session autostarts) needs
+/// - a focus-following clipboard manager is impossible without it.
+impl DataControlHandler for CompState {
+    fn data_control_state(&self) -> &DataControlState {
+        &self.data_control_state
+    }
+}